This software was developed by Arni Fannar Sigurdsson, of arnifannar.com. It was released online on the 4th of October 2021, as a web service to be openly available to public use through the website. All coding and graphic design was done by the developer himself. Information on the biomechanics and the kinetics of the physical exercises referenced in the system has been gathered from written sources (ref) and private consultation with practitioners and enthusiasts of workout. There are no claims in the software that it is offering any guidance or advice on how to safely perform these exercises.
The AF WORKOUT CALCULATOR is a software that is available to be used, free of charge, from the website of its developer, arnifannar.com. The software contains records of physical exercises, in the form of illustrations of muscle engagement from each exercise. The software offers the users to combine exercises from the record to produce an estimate of the distribution of strain from entire workout sessions. The estimated strain is broadly based on the role of each muscle in each exercise (as either agonist, synergist, antagonist, or a stabilizer). The outcome can then be saved to a user-specific calendar, where a user can then add details on number of repetitions and weights. This way, users can keep track of their long-term workout. This version of the software only provides information on a generic level and does not give any recommendations to users on which exercises to perform. It should be noted that muscle recruitment, from any physical exercise, is dependent on form and can vary between individuals.
The range of exercise that are available in the AF WORKOUT CALCULATOR is limited to strength-training exercises:
exercises where muscles are used for short bursts of great strength, recruiting fast-twitch muscle fibers, or anaerobic exercises,
which stimulate muscle growth. [1]
The system typically offers options of basic variations for each exercise,
in terms of equipment and position of the body. These variations do not always affect the estimated muscle engagement on the level
of accuracy and precision that the system can reasonably offer. The purpose of the variations is rather to provide accuracy in users’
registration of their performed exercises.
The AF WORKOUT CALCULATOR introduces a specialized heatmap figure to demonstrate muscle engagement interactively. Muscle engagement from a single exercise is displayed with the heatmap figure colored in different shades of red and a single shade of orange. The different coloring represents the different roles of muscles in an exercise, where agonists/primary movers are painted with the strongest shade of red, and lighter shades of red indicate roles of muscles as synergists, dynamic stabilizers, antagonists, or primary movers of secondary movements in an exercise, respectively. Stabilizers are colored orange. The generated heatmap figure from user input of selected exercise , on the other hand, has only shades of red, where the stabilizers are the lightest shade. The resulting heatmap averages the strength of red for each muscle from the exercises. It is a simplistic way of estimating muscle engagement, which is only intended to give the user a generic overview.
Using the basic exercise ‘bench presses with a barbell’, as an example, the pectoralis major muscles are primary movers, so they are colored in the strongest shade of red. The anterior deltoids have been categorized as synergists and stabilizers [2], as well becoming primary movers as taking over as primary movers at maximum load[3]. These muscles are thus given an intermediary role, between synergists and agonists, with a shade of red that’s in between the two roles. The only muscles that is counted as a straight-forward synergist here is the anconeus and coracobrachialis. Other engaged muscles are the same shade of red, except for the abdominal muscles, the trapezius muscles and some of the forearm muscles. Other muscles that are classified as stabilizers for this exercise, such as, the rotator cuffs, erector spinae, and the middle and posterior deltoids are colored orange, or with the lightest shade of red when the exercise is registered.
Visitors of the site are offered to create their own user accounts, which will enable them to save their workout, in the form of generated heatmaps along with a list of exercises, into a calendar. From the calendar, the users can then add information about sets, weights and repetitions, which will not affect the heatmap. The user authentication process is done through a specialized service and the developer does not have access to passwords that are used.
[1] Boakes, Jennette L. & Rab, George T. (2006) Muscle Activity During Walking. Appears in: Human Walking. Lippincott Williams & Wilkins
[2] McCaw S T, Friday J J. A comparison of muscle activity between free weight and machine bench press. J Strength Cond Res. 1994;8:259–264.
[3] Król H, Gołaś A. Effect Of Barbell Weight On The Structure Of The Flat Bench Press. Journal of Strength and Conditioning Research. 2017;31(5):1321-1337.
The information on muscle strain from exercises has been compiled from a variety of sources, ranging from published books on kinetics or biomechanics, and research articles, to blog posts on fitness-themed websites, and information from personal contacts, for a variety of perspectives. Below is a list of the sources of listed published books, research articles and blog posts.
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Burden, Adrian; G. Redmond, Colin. (2013) Abdominal and Hip Flexor Muscle Activity During 2 Minutes of Sit-Ups and Curl-Ups. Journal of Strength and Conditioning Research. August. 27(8), 2119-2128.
Cacchio, Angelo; Don, Romildo; Ranavolo, Alberto; Guerra, Enrico; Mccaw, Steven; Procaccianti, Rita; Camerota, Filippo; Frascarelli, Massimo; Santilli, Valter (2008). Effects of 8-week strength training with two models of chest press machines on muscular activity pattern and strength. Journal of electromyography and kinesiology: official journal of the International Society of Electrophysiological Kinesiology, 18.
Calatayud, J.; Colado, J. C.; Martin, F.; Casaña, J., Jakobsen; M. D.; Andersen, L. L. (2015). Core Muscle Activity During the Clean and Jerk Lift with Barbell Versus Sandbags and Water Bags. International journal of sports physical therapy, 10(6), 803–810.
Contreras, Bret; Schoenfeld, Brad; Mike, Jonathan; Tiryaki-Sonmez, Raziye; Cronin, John; Vaino, Elsbeth. (2012). The Biomechanics of the Push-up. Strength and Conditioning Journal, 34(10).
Cotterman, Michael L.; Darby, Lynn A.; and Skelly; William A. (2005) Comparison of Muscle Force Production Using the Smith Machine and Free Weights for Bench Press and Squat Exercises. Journal of Strength and Conditioning Research, 19(1), 169-176.
Delavier, Frédéric (2010) Strength Training Anatomy. Third edition. Human Kinetics.
Delavier, Frédéric & Gundill, Michael. (2010) Delavier's Core Training Anatomy. Human Kinetics.
Delavier, Frédéric & Gundill, Michael. (2011) The Strength Training Anatomy Workout. Human Kinetics.
Erdmann WS. (2018) Center of mass of the human body helps in analysis of balance and movement. MOJ App Bio Biomech, 2(2), 144–148.
Fenwick, Chad; Brown, Stephen; McGill, Stuart (2009) Comparison of Different Rowing Exercises: Trunk Muscle Activation and Lumbar Spine Motion, Load, and Stiffness. Journal of Strength and Conditioning Research, 23(5), 1408-1417.
Huang, T. W. & Kuo, A. D. (2014). Mechanics and energetics of load carriage during human walking. The Journal of experimental biology, 217(Pt 4), 605–613. https://doi.org/10.1242/jeb.091587
Johnson, Doug; Lynch, James; Nash, Cygan; Mayhew, Jerry. (2009) Relationship of Lat-Pull Repetitions and Pull-Ups to Maximal Lat-Pull and Pull-Up Strength in Men and Women. Journal of Strength and Conditioning Research, 23(3), 1022-1028.
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https://bodyweighttribe.com/what-muscles-do-dips-work-more-chest-or-tricep/
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https://drummondeducation.com/forensic-analysis-shoulder-press/
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https://exrx.net/WeightExercises/Other/SBFarmersWalk
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https://fitnessvolt.com/24618/dumbbell-step-up/
https://fitnessvolt.com/cable-twist-obliques/
https://fitnessvolt.com/chest-press-vs-bench-press/
https://fitnessvolt.com/dumbbell-front-raise/
https://www.healthline.com/health/4-kinetic-chain-exercises
https://www.healthline.com/health/fitness/australian-pull-up
https://www.healthline.com/health/fitness/what-muscles-do-planks-work
https://www.healthline.com/health/fitness-exercise/lower-back-exercises
https://www.healthline.com/health/seated-row#muscles-used
https://www.healthline.com/nutrition/farmers-walk-benefits
https://www.livestrong.com/article/405269-vastus-lateralis-intermedius-exercises/
https://www.livestrong.com/article/533901-the-muscles-used-in-the-farmers-walk-exercise/
https://www.livestrong.com/article/540887-what-muscles-do-bicycle-crunches-work/
https://livehealthy.chron.com/can-biceps-curls-strengthen-shoulder-8521.html
https://www.menshealth.com/fitness/a28008112/leg-extensions/
https://www.menshealth.com/uk/building-muscle/a33643012/tricep-dips/
https://www.oldschoollabs.com/hammer-curls-vs-bicep-curls/
https://www.onnit.com/academy/bent-over-row/
https://pilatesfitness.com.sg/lateral-flexion-side-bend-best-lower-back-pain-treatment/
https://www.prevention.com/fitness/fitness-tips/a28747774/muscles-planking-exercise/
https://www.shapefit.com/exercise-guides/middle-back-exercises-smith-machine-bent-over-rows.html
https://www.stack.com/a/stabilizer-muscles-what-they-are-and-why-theyre-so-important/
https://www.strengthlog.com/clean-and-jerk/
https://www.strengthlog.com/hip-adductor-muscles-exercises-workout/
https://origympersonaltrainercourses.co.uk/blog/tricep-pushdown
https://www.sportsrec.com/200099-shoulder-adduction-exercises.html
https://www.verywellfit.com/how-to-perform-the-reverse-fly-4684392
https://www.verywellfit.com/how-to-perform-the-trx-biceps-curl-4589435
https://www.yorkvillesportsmed.com/blog/top-rotator-cuff-exercises-for-stretches-strengthening
Ingebrigtsen, Jørgen; Holtermann, Andreas; Roeleveld, Karin. (2009) Effects of Load and Contraction Velocity During Three-Week Biceps Curls Training on Isometric and Isokinetic Performance. Journal of Strength and Conditioning Research, 23(6), 1670-1676.
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Król, H., & Gołaś, A. (2017). Effect of Barbell Weight on the Structure of the Flat Bench Press. Journal of strength and conditioning research, 31(5), 1321–1337. https://doi.org/10.1519/JSC.0000000000001816
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